1. Field of the Invention
The present invention generally relates to a condensed polycyclic compound and a light emitting device using the same.
2. Description of the Related Art
Recent progress in the development of organic light emitting devices has been remarkable, and includes the development of relatively high brightness at a fairly low applied voltage, diversification of the wavelength of the emitted light, high-speed response, and a reduction in the thickness and weight of the light emitting device. From this, the organic light emitting device appears to show promise for broader use.
However, there remains a need for the development of optical power with increased brightness or higher conversion efficiency. In addition, there remains a need for improvement in aspects such as durability, to reduce deterioration that can occur with use over long periods of time, and to reduce deterioration by atmospheric gas containing oxygen and/or moisture. Furthermore, in the case of application to full color displays, there remains a need for emission of blue, green and red lights with increased color purity.
Some studies have been conducted on aromatic compounds and condensed polycyclic aromatic compounds as fluorescent organic compounds usable as materials that constitute the light emitting layer, electron transport layer and the like. However, compounds having fully satisfactory light emission brightness and durability have not yet been obtained.
Japanese Patent Application Laid-Open No. 2003-347058, WO2005/040303, and WO2004/043901 disclose examples of aromatic compounds and condensed polycyclic aromatic compounds as materials that constitute organic light emitting devices. Also, Japanese Patent Application Laid-Open No. 2003-347058, WO2005/040303, and WO2004/043901 disclose the application of certain condensed polycyclic aromatic compounds to organic light emitting devices.
Accordingly, in order to achieve satisfactory performance of organic light emitting devices in display apparatuses, such as display screens, an enhancement in the durability of the devices may need to be obtained.